I've successfully restored several times, most recently last week. TM is a lifesaver.

every restore I've done has worked successfully

Me too! I have never used it for my own backups, but at least 6-7 times a family member (for whom I am de facto emergency tech support) has called me with a borked Mac and a Time Machine backup. In every single instance the restore operation has failed.

(Most common failure mode is to like appear to be working for hours/overnight, then say something helpful like "Unable to restore Time Machine backup").

Backup is the very last thing I would trust Apple to do.